MEMS device and inertial measurement unit

The present application is based on, and claims priority from JP Application Serial Number 2022-174228, filed Oct. 31, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.

The present disclosure relates to a MEMS device, an inertial measurement unit, etc.

JP-A-2021-032819 discloses a structure of a MEMS device detecting an acceleration in Z directions. In the structure, a length of a first electrode along first directions of one of a plurality of first electrodes is shorter than a length of a first conducting portion along first directions of the first conducting portion, and a length of a second electrode along first directions of one of a plurality of second electrodes is shorter than a length of a second conducting portion along first directions of the second conducting portion.

In the MEMS device disclosed in JP-A-2021-032819, in order to obtain excellent sensor characteristics, it is necessary to consider routing of wires to a movable electrode and a fixed electrode for detecting capacity.

An aspect of the present disclosure relates to a MEMS device including a substrate, a fixed electrode portion fixed relative to the substrate, a movable body movable relative to the substrate, a fixed electrode fixing portion electrically coupled to the fixed electrode portion, a wiring structure provided in a same layer as those of the movable body and the fixed electrode portion with respect to the substrate, and a first wire having one end coupled to the fixed electrode fixing portion, wherein the wiring structure is at least provided in an opening part of the movable body, and the first wire is wired on the wiring structure via an insulating film and routed out of the movable body through the opening part of the movable body.

Further, another aspect of the present disclosure relates to an inertial measurement unit including the above described MEMS device, and a control unit performing control based on a detection signal output from the MEMS device.

As below, embodiments will be explained. Note that the following embodiments do not unduly limit the description of What is Claimed is. Further, not all configurations described in the embodiments are necessarily essential component elements.

1. MEMS Device

A MEMS (Micro Electro Mechanical Systems) deviceof the embodiment will be explained using an acceleration sensor detecting an acceleration in a vertical direction as an example.is a plan view of the MEMS deviceof the embodiment in a plan view in a direction orthogonal to a substrate. The MEMS deviceis e.g., an inertial sensor.

Note that, inand, which will be described later, for convenience of explanation, dimensions of respective members, distances between the members, etc. are schematically shown and not all component elements are shown. As below, a case where a physical quantity detected by the MEMS deviceis an acceleration is mainly explained as an example, however, the physical quantity is not limited to the acceleration, but may be another physical quantity such as a velocity, pressure, displacement, attitude, angular velocity, or gravity force. Further, directions orthogonal to one another inare a first direction DR, a second direction DR, and a third direction DR. The first direction DR, the second direction DR, and the third direction DRare e.g., an X-axis direction, a Y-axis direction, and a Z-axis direction, respectively, however, not limited to those. For example, the third direction DRcorresponding to the Z-axis direction is a direction orthogonal to the substrateof the MEMS deviceand the vertical direction. An opposite direction to the third direction DRis a fifth direction DR. The first direction DRcorresponding to the X-axis direction and the second direction DRcorresponding to the Y-axis direction are directions orthogonal to the third direction DR, an XY-plane as a plane along the first direction DRand the second direction DRare along e.g., a horizontal plane. An opposite direction to the first direction DRis a fourth direction DRand the fourth direction is e.g., the −X-axis direction. Note that “orthogonal” includes not only an intersection at 90° but also intersections at angles slightly inclined from 90°.

As shown in, the MEMS deviceof the embodiment includes the substrate, fixed electrode portions,, a movable body MB, fixed electrode fixing portions,, a wiring structure SA, and first wires L, L. The fixed electrode portionhas a plurality of fixed electrodesand the fixed electrode portionhas a plurality of fixed electrodes. The movable body MB includes movable electrode portions,. The movable electrode portionof the movable body MB includes movable electrodesand the movable electrode portionsinclude movable electrodes.

The substrateis e.g., a silicon substrate formed using semiconductor silicon, a glass substrate formed using a glass material such as borosilicate glass, or the like. As the substrate, specifically, an SOI (Silicon On Insulator) substrate may be used. As will be described later in, an insulating layer I is provided on the silicon substrate and a structure layer of a silicon material or the like is provided in an upper layer thereof.

The movable body MB is movable relative to the substratewith an acceleration or the like applied from outside in the MEMS device. As shown in, the MEMS devicemay include supporting beamsand fixing portions, and the movable body MB is coupled to the substratevia the supporting beamsand the fixing portions. The supporting beamis e.g., a tortional spring. Further, as will be described later in, the fixing portionis coupled to the substratevia an insulating film D. One end of the supporting beamis coupled to the fixing portionand the other end thereof is coupled to the movable body MB.

As described above, the MEMS deviceof the embodiment includes the supporting beamswith one ends coupled to the fixing portionsand the other ends coupled to the movable body MB. The fixing portionsare electrically coupled to the movable body MB via the supporting beams. According to the configuration, the supporting beamstwist according to the acceleration or the like applied from outside, and thereby, the movable body MB may make a see-saw motion with respect to the substrate.

As shown inetc., cavities CA are provided at the side in the −Z direction of the movable body MB, i.e., at the side in the opposite direction to the third direction DR. The cavity CA is a space of a part of the substraterecessed toward the −Z direction, i.e., the side in the opposite direction to the third direction DR. By the cavities CA provided in the substrate, the movable body MB may may make a see-saw motion without contacting the substrate. Note that the movable body MB is not necessarily directly coupled to the substrate, but, for example, in a gyro sensor to be described inor the like, coupled to the substratevia a vibrator.

The fixed electrode portions,serve to detect an acceleration in the MEMS devicewith the movable electrode portions,of the movable body MB. As shown in, the fixed electrode portions,are fixed relative to the substrate. As shown in, at the side in the first direction DRof the MEMS device, the plurality of fixed electrodesof the fixed electrode portionare provided to face the plurality of movable electrodesof the movable electrode portion. Further, at the side in the fourth direction DRof the MEMS device, the plurality of fixed electrodesof the fixed electrode portionare provided to face the plurality of movable electrodesof the movable electrode portion. As described in, the fixed electrode, the movable electrode, the fixed electrode, and the movable electrodeare plate-like shapes along the third direction DRand these electrodes are placed to face each other. Furthermore, the fixed electrodeand the movable electrode, and the fixed electrodeand the movable electrodeare configured to respectively serve as probes and detect a physical quantity such as an acceleration.

That is, in the embodiment, the fixed electrode portions,include the fixed electrodes,facing the movable electrodes,provided in the movable body MB. According to the configuration, in the MEMS device, the probes detecting a physical quantity may be formed. Note that, hereinafter, the fixed electrodes,and the movable electrodes,are appropriately and collectively referred to as “probe electrodes”.

Further, an area where the fixed electrodesand the movable electrodesface to form the probes is referred to as “detection part Z” and an area where the fixed electrodesand the movable electrodesface to form the probes is referred to as “detection part Z”. As described above, in the MEMS deviceof the embodiment, at least one or more detection parts are provided by the fixed electrodes,and the movable electrodes,and, in the example shown in, the detection part Zis provided at the side in the first direction DRin the plan view and the detection part Zis provided at the side in the fourth direction DRin the plan view. Note that, hereinafter, the detection part Zand the detection part Zare appropriately collectively referred to as “respective detection parts”.

The fixed electrode fixing portionfixes the fixed electrode portionand the fixed electrode fixing portionsfix the fixed electrode portionsrespectively to the substrate. As shown in, one end of the fixed electrode fixing portionis coupled to the substrateand another part thereof is coupled to the fixed electrode portion. Further, one ends of the fixed electrode fixing portionsare coupled to the substrateand other portions thereof are coupled to the fixed electrode portions. As described above, the fixed electrodesof the fixed electrode portionand the fixed electrodesof the fixed electrode portionsare fixed in certain positions with respect to the substrate. Note that the fixed electrode fixing portionis also electrically coupled to the fixed electrode portionand the fixed electrode fixing portionsare also electrically coupled to the fixed electrode portions. Further, the fixed electrode fixing portions,may have cantilevered structures or fixed to the substrateto the bases of the fixed electrode portions,. As shown in, in the MEMS deviceof the embodiment, the fixing portionsand the fixed electrode fixing portions,are placed concentratedly near the center of the MEMS devicein the plan view. Note that, hereinafter, the fixed electrode fixing portionand the fixed electrode fixing portionsare appropriately collectively referred to as “fixed electrode fixing portions”.

Further, the MEMS deviceof the embodiment may include a stopper structure SB and a shield structure SC. The stopper structure SB suppresses an excessive motion of the movable body MB. The stopper structure SB is configured to surround the movable body MB by at least three sides in the plan view as shown in. In the example shown in, the stopper structure SB has a shape surrounding by the three sides of the movable body MB at the side in the first direction DR, the side in the second direction DR, and the side in the opposite direction to the second direction DR. For example, when excessively displaced toward the side in the first direction DR, the movable body MB collides with a configuration portion provided along the second direction DRof the stopper structure SB, and thereby, the excessive displacement is suppressed. Excessive displacements in the other directions are suppressed in the same manner. The stopper structure SB may be formed using a conductive material e.g., impurity-doped silicon. Further, as shown into be described later, the stopper structure SB is provided on the substratevia the insulating film D and insulated from the substrate. As shown into be described later, the stopper structure SB is provided in the same layer as those of the probe electrodes including the fixed electrodes,and the movable electrodes,in the sectional view. Here, the same layer refers to the same level at which the height in the third direction DRwith respect to the substrateis shown in the sectional view of the MEMS device. That is, the stopper structure SB is provided in the same layer as those of the probe electrodes even when the height thereof in the third direction DRwith respect to the substrateis not equal to those of the probe electrodes as long as the height falls within a certain range.

The shield structure SC electrically shields the movable body MB and the stopper structure SB from outside. As shown in, the shield structure SC is configured to further surround the stopper structure SB surrounding the movable body MB in the plan view. The shield structure SC is set at e.g., the ground potential. The shield structure SC is set at the ground potential, and thereby, external electric and magnetic influences may be suppressed, the movable body MB and the stopper structure SB inside of the shield structure SC may be maintained to be electrically and magnetically stable, and high-accuracy physical quantity detection can be realized in the detection parts Z, Z. The shield structure SC may be formed using a conductive material e.g., impurity-doped silicon like the stopper structure SB. The shield structure SC is also provided on the substratevia the insulating film D in the same layer as those of the probe electrodes in the sectional view. Note that, hereinafter, the stopper structure SB and the shield structure SC provided outside of the movable body MB are appropriately collectively referred to as “structure SBC”.

The first wires L, Ltransmit the detection signals of the fixed electrode portions,to fixed electrode terminals T, T, respectively. One end of the first wire Lis coupled to the fixed electrode fixing portionand the other end thereof is coupled to the fixed electrode terminal T. The first wire Ltransmits the signal detected by the fixed electrode portionin the detection part Zto the fixed electrode terminal T. Further, one ends of the first wires Lare coupled to the fixed electrode fixing portionsand the other ends thereof are coupled to the fixed electrode terminal T. Conductive materials may be used for the first wires L, L, and the first wires are provided on the wiring structure SA via the insulating film D, for example, as shown inetc. The first wires Ltransmit the signals detected by the fixed electrode portionsin the detection part Zto the fixed electrode terminal T. Note that, hereinafter, the first wires L, Lare appropriately collectively referred to as “first wires L”.

In the embodiment, as shown in, a second wire Land a movable electrode terminal Tmay be provided. The second wire Lelectrically couples the above described fixing portionsand the movable electrode terminal T. The fixing portionshave roles of anchors for the movable body MB and are electrically coupled to the movable body MB. The movable body MB includes the movable electrodes,of the movable electrode portions,. Therefore, the movable electrodes,of the movable electrode portions,are electrically coupled to the movable electrode terminal Tvia the second wire L. A conductive film may be used for the second wire Llike the first wires Land the second wire is provided on the wiring structure SA via the insulating film D.

That is, the MEMS deviceof the embodiment includes the fixing portionselectrically coupled to the movable body MB and the second wire Lhaving the one end coupled to the fixing portions. The second wire Lis wired on the wiring structure SA via the insulating film D and routed out of the movable body MB through an opening part OP of the movable body MB. According to the configuration, voltages of the movable electrodes,of the movable body MB may be controlled by a voltage applied to the movable electrode terminal T. Note that, hereinafter, the first wires L, Land the second wire Lare appropriately collectively referred to as “respective wires”.

The wiring structure SA is a structure provided in the opening part OP of the movable body MB. As shown in, the opening part OP is an area opened from the vicinity of the center of the movable body MB to the outside of the movable body MB in the plan view. Here, the direction outward from the center is the fourth direction DRin the example shown in, however, may be any direction. The wiring structure SA is provided at least in the opening part OP in the plan view. In the configuration example shown in, the wiring structure SA is provided not only in the opening part OP but also along the fixed electrode portions. As described above, the wiring structure SA is provided at least in the opening part OP and may be optionally provided in another area. Further, the wiring structure SA is provided in the same layer as those of the fixed electrodes,, the movable electrodes,, the stopper structure SB, and the shield structure SC in the sectional view as shown into be described later. Furthermore, the wiring structure SA is provided between the wires including the first wires L, the second wire L, etc. in the upper layer and the substratein the lower layer via the insulating film D. Therefore, the wiring structure SA is electrically insulated from the wires provided in the upper layer and the substrate in the lower layer. The wiring structure SA may be formed using a conductive material e.g., impurity-doped silicon like the stopper structure SB and the shield structure SC. Note that, hereinafter, the same layer as those of the movable body MB, the wiring structure SA, the stopper structure SB, the shield structure SC, etc. is referred to as “structure layer”. The wiring structure SA is integrally formed with the shield structure SC.

As described above, according to the MEMS deviceof the embodiment, in a capacitive device formed using the cavity SOI process, the respective wires including the first wires L, the second wire L, etc. are provided on the wiring structure SA via the insulating layer D, and the fixed electrode fixing portions,as the anchors for the fixed electrode portions,are located inside of the movable body MB in the plan view. Further, the respective wires may be routed from the opening part OP provided in the movable body MB. Further, for example, the stopper structure SB at the same potential as that of the movable body MB is placed around the three or more sides of the movable body MB. The wiring structure SA provided within the opening part OP is fixed at the ground or the same potential as that of the movable body MB.

Next, a basic motion of the MEMS deviceis explained.shows sectional views of the MEMS devicealong a dotted line a in. Note that, in, the description of the component elements unnecessary for explanation of the basic motion of the MEMS deviceis omitted. In, the sectional view in an initial state is shown in the upper part and the sectional view in a state with an acceleration is shown in the lower part.

First, the initial state shown in the upper part ofis a resting state and the movable electrodeprovided in the detection part Zand the movable electrodeprovided in the detection part Zrest in the positions at the same height relative to the substrate. In this regard, the opposed face area of the fixed electrodeand the movable electrodein the detection part Zand the opposed face area of the fixed electrodeand the movable electrodein the detection part Zare equal.

The state with an acceleration shown in the lower part inis a state with an acceleration in the third direction DR, i.e., the +Z direction. Here, in the MEMS deviceshown in, the opening part OP is provided at the side in the fourth direction DRof the supporting beamsas a rotation axis of the movable body MB and inertia moment of the movable body MB is smaller at the side in the fourth direction DRof the supporting beams. Therefore, when an acceleration in the +Z direction is applied, the movable electrodeprovided at the side in the first direction DRand having higher rotation sensitivity is subjected to an inertial force in the opposite direction to that of the acceleration and displaced toward the opposite direction to the third direction DR, i.e., the −Z direction. Further, the movable electrodeprovided at the side in the fourth direction DRof the supporting beamsis displaced in the +Z direction as the opposite direction to that of the movable electrodes. In this case, as shown in the lower part of, the opposed face area of the fixed electrodeand the movable electrodeis maintained substantially constant in the detection part Z, and the opposed face area of the fixed electrodeand the movable electrodedecreases in the detection part Z. On the other hand, when an acceleration in the −Z direction is applied, the movable electrodeat the side of the larger inertial moment is subjected to an inertial force in the +Z direction and displaced in the +Z direction and the movable electrodeis displaced in the same direction as that of the acceleration, and thereby, the opposed face area of the probe electrodes decreases in the detection part Zand the opposed face area of the probe electrodes is maintained substantially constant in the detection part Z. As described above, when an acceleration in either the +Z direction or the −Z direction is generated in the MEMS device, the opposed face area changes in either the detection part Zor Z.

schematically shows a measurement system of the MEMS device. As described in, the MEMS deviceof the embodiment detects a physical quantity such as an acceleration as e.g., a change of the opposed face area of the probe electrodes. Further, the opposed face area of the probe electrodes may be detected as e.g., a change of capacitance. In, a capacitance CZcorresponds to a capacitance of a capacitor formed by the probe electrodes provided in the detection part Zand a capacitance CZcorresponds to a capacitance of a capacitor formed by the probe electrodes provided in the detection part Z. The fixed electrodesin the detection part Zare coupled to the fixed electrode terminal Tvia the first wire L, and the movable electrodesin the detection part Zare coupled to the movable electrode terminal Tvia the second wire L. The fixed electrodesin the detection part Zare coupled to the fixed electrode terminal Tvia the first wires L, and the movable electrodesin the detection part Zare coupled to the movable electrode terminal Tvia the second wire L.

That is, the MEMS deviceof the embodiment includes the fixed electrode terminals T, Tcoupled to the first wires L, Land the movable electrode terminal Tcoupled to the second wire L. According to the configuration, the capacitance CZin the detection part Zand the capacitance CZin the detection part Zmay be detected from the fixed electrode terminals T, Tand the movable electrode terminal T.

is a diagram for explanation of a potential relationship among the respective component elements regarding the MEMS deviceof the embodiment. Specifically,shows the potential relationship among the respective component elements in a schematic sectional view along a dashed-dotted line b in. Note that, in, the individual component elements are schematically shown. For example, the first wire Land the first wires Lare collectively shown as one first wire L. Further, the stopper structure SB and the shield structure SC provided outside of the movable body MB may take various placement patterns as will be described inand the subsequent drawings, and these structures are collectively referred to as the structure SBC. As shown in, the potentials of the first wire Land the second wire Lare VLand VL, the potential of the wiring structure SA is VSA, the potential of the movable body MB is VZ, the potential of the structure SBC provided outside of the movable body MB is VSBC. In the embodiment, when the capacitance is detected, applied voltages may be controlled with respect to not only the potentials VL, VLof the respective wires and the potential VZ of the movable body MB but also the potential VSA of the wiring structure SA and the potential VSBC of the structure SBC provided outside of the movable body MB. For example, the potential VSA of the wiring structure SA may be set to the ground or the same potential as that of the movable body MB. As described above, in the embodiment, the physical quantity detection is performed using not only the potential control of the probe electrodes of the fixed electrodes,, the movable electrodes,, etc. directly used for the physical quantity detection but also the potential control of the wiring structure SA adjacent thereto, the stopper structure SB, the shield structure SC, etc. provided outside of the movable body MB.

are diagrams for explanation of the MEMS deviceof the embodiment by comparisons with a comparative example thereof.shows a schematic diagram of a section structure of the MEMS devicealong the dashed-dotted line b inand the comparative example thereof. Note that, regarding, like, the individual component elements are schematically shown and not all component elements are displayed. A configuration A shown in the upper part ofis an example in which the wiring structure SA is not provided in the opening part OP like that in the MEMS deviceof the embodiment and the respective wires of the first wire Land the second wire Lare provided in the same layer as those of the detection parts Z, Z. A configuration B shown in the lower part ofcorresponds to the embodiment. In the sectional shape of the configuration B, the wiring structure SA is provided in the opening part OP as described above, and the respective wires are placed thereon via the insulating layer D. In the configuration B, the potential of the wiring structure SA is controlled to be a fixed potential e.g., the ground.

As described in, in the embodiment, a physical quantity such as an acceleration is detected based on the capacitances CZ, CZbetween the probe electrodes in the detection parts Z, Z, and other capacitances than the capacitances CZ, CZare generated between the respective component elements. For example, in both the configuration A and the configuration B in, a capacitive coupling CLZ is generated between the first wire Land the movable body MB and a capacitive coupling CLL is generated between the first wire Land the second wire L.shows how the capacitive couplings CLZ, CLL described inappear in the measurement system of the MEMS deviceof the embodiment described in. As shown in, the capacitive couplings CLZ, CLL are generated in parallel to the capacitances CZ, CZ.

As described above, in addition to the capacitances in the probe electrodes used for physical quantity detection, the capacitive couplings CLZ and the capacitive couplings CLL are generated. It is necessary to consider the influences on the physical quantity detection by these capacitive couplings in the MEMS device. Regarding the capacitive coupling CLL, when the respective wires are provided in the same layer as those of the respective structures like those in the configuration A, the sections of the respective wires are larger and the capacitive coupling CLL is larger. On the other hand, according to the configuration B, the respective wires are provided on the wiring structure SA via the insulating layer D and, compared to the sections of the configuration A, the sections of the respective wires may be made smaller. Therefore, the capacitive couplings CLL and the capacitive couplings CLZ between the respective wires and the movable body MB are smaller and the influences on the physical quantity detection in the MEMS devicemay be suppressed.

is a sectional view of the respective wires and the wiring structure SA as seen at the side in the first direction DR. Electric fields generated between the first wire Land the second wire Linclude electric fields parallel to the horizontal plane and fringe electric fields generated to come around from the upper end or the lower end of the wires. Here, the fringe electric fields are compared between the configuration A and the configuration B. In the configuration A, the fringe electric fields according to dielectric constants of the materials between wires are generated at both the upper end side and the lower end side of the respective wires, and accordingly, capacitance couplings based on the fringe electric fields are generated. On the other hand, in the configuration B, the electric fields are the same at the upper end side of the respective wires as the configuration A, however, at the lower end side of the respective wires, generation of the fringe electric fields may be suppressed because the conductive material such as silicon is used as the wiring structure SA. Thereby, the capacitance couplings between the respective wires with the fringe electric fields may be suppressed. Therefore, the first wire Land the second wire Lare not directly provided in the same layer as those of the respective detection parts as in the configuration A, but the respective wires are provided on the conductive wiring structure SA as in the configuration B, and thereby, the fringe electric fields around the lower end side of the respective wires may be suppressed and unnecessary capacitance couplings may be suppressed. Here, when the wiring structure SA is set to be floated, the wiring structure SA is electrically charged and an unnecessary and uncontrollable electrostatic force is generated between the movable body MB and itself. Therefore, a configuration in which the wiring structure SA is set at a predetermined potential such as the ground is employed like the configuration B, and thereby, the above described defect may be suppressed. The wiring structure SA is set at a predetermined potential such as the ground like the configuration B, and thereby, an effect of suppressing not only the capacitive couplings CLL by the fringe electric fields between the wires but also the capacitive couplings CLZ between the respective wires and the movable body MB may be obtained. Note that, as above, the case where an out-of-plane rotation physical quantity sensor is provided inside of the stopper structure SB is explained as an example, however, the same effect may be obtained in cases where various physical quantity sensors are provided.

In the MEMS device disclosed in JP-A-2021-032819, as a technique of making contact between the probe electrodes and terminals, TSV (Through Silicon Via) may be employed. Specifically, pads are provided directly above the structure layer fixed to the substrate and the contact with the pads may be made by vias across the layers. When the TSV is employed, it is necessary to increase the areas of the anchors as the fixing portions of the structure for contact with the pads and it is not easy to concentratedly place the anchors in a part within the MEMS device. Further, problems of fluctuations in characteristics and increase in cost due to junction stress of the contact are caused. As described above, the TSV may avoid the problems of increase in element area due to routing of wires because the contact with the probe electrodes may be made by via contact, however, concentrated placement of the anchors in a part is difficult. If the anchors are dispersedly provided, the anchors are susceptible to the influence of warpage of the substrate due to external stress and temperature changes and the detection characteristics of the MEMS device are degraded. In this regard, in the embodiment, the TSV is not employed, but the opening part OP extending around from the vicinity of the center of the MEMS deviceis provided and the respective wires are collectively placed on the wiring structure SA provided in the opening part OP, and thereby, the wiring efficiency is increased. Without using the TSV, the anchors may be concentratedly placed near the center of the MEMS deviceand the anchors are less susceptible to the influence of warpage of the substratedue to external stress and temperature changes. Therefore, the high-accuracy MEMS devicemay be realized.

That is, the MEMS deviceof the embodiment includes the substrate, the fixed electrode portions,, the movable body MB, the fixed electrode fixing portions, the wiring structure SA, and the first wire L. The fixed electrode portions,are fixed relative to the substrate. The movable body MB is movable relative to the substrate. The fixed electrode fixing portionsare electrically coupled to the fixed electrode portions,. The wiring structure SA is provided in the same layer as those of the movable body MB and the fixed electrode portions,with respect to the substrate. One end of the first wire Lis coupled to the fixed electrode fixing portions. The wiring structure SA is provided at least in the opening part OP of the movable body MB and the first wire Lis wired on the wiring structure SA via the insulating film D and routed out of the movable body MB through the opening part OP of the movable body MB.

According to the configuration, in the MEMS deviceformed using the SOI process or the like, the first wire Lis provided in the same layer as that of the wiring structure SA via the insulating film D, the anchors of the fixed electrode portions,are located inside of the movable body MB, and the wires may be routed from within the opening part OP provided in the movable body MB. Accordingly, the wiring efficiency may be increased and the area assigned to the probe electrodes in the plan view may be increased. Therefore, downsizing is easier than the MEMS devicehaving the same size and the same sensitivity. Further, when an out-of-plane rotation physical quantity sensor is provided inside of the stopper structure SB, the opening part is provided at the movable body MB side with smaller rotation torque and the wires are routed, and thereby, the rotation torque is increased and higher sensitivity and further downsizing can be realized.

In the embodiment, the wiring structure SA is set at the ground potential. According to the configuration, degradation of capacitance offsets due to generation of an unnecessary capacitance between the fixed electrode portionand the movable electrode portionor the fixed electrode portionand the movable electrode portionmay be suppressed and high-accuracy physical quantity detection can be performed.

Further, in the embodiment, the potential VSA of the wiring structure SA may be set to the same potential as that of the movable body MB. The potential of the movable body MB is e.g., the potential of the movable electrode portions,.

That is, in the embodiment, the wiring structure SA is set at the same potential as that of the movable body MB. According to the configuration, the movable electrode portions,and the wiring structure SA are at the same potential, and thereby, no capacitance is generated between the movable electrode portions,and the wiring structure SA, an unnecessary capacitance component parasitic in the capacitance in the probe electrodes may be reduced, and the high-accuracy MEMS devicemay be realized.

The MEMS deviceof the embodiment includes the shield structure SC provided to surround the movable body MB and set at the ground potential. The wiring structure SA is integrally formed with the shield structure SC.

According to the configuration, external electric and magnetic influences on the MEMS devicemay be blocked and the high-accuracy physical quantity detection can be performed. Further, the wiring structure SA is integrally formed with the shield structure SC, and thereby, the potential of the wiring structure SA may be constantly fixed to the ground potential. The first wire L, the second wire L, etc. provided in the upper layer of the wiring structure SA are electrically stabilized and the high-accuracy physical quantity detection can be performed.

In the embodiment, the movable body MB, the fixed electrode portions,, and the wiring structure SA are formed using silicon. According to the configuration, the movable body MB and the fixed electrode portions,may be formed using silicon having conductivity. Therefore, the physical quantity such as a capacitance can be detected in the probes. Further, the wiring structure SA may be formed using silicon having conductivity, and the potential of the lower portions of the respective wires may be fixed to certain potentials by control of the potential of the wiring structure SA. Therefore, propagations of the electrical signals of the respective wires may be stabilized and the high-accuracy physical quantity detection can be performed. Further, all of the movable body MB, the fixed electrode portions,, and the wiring structure SA are formed in the same layer and these are formed using the same silicon, and thereby, deposition and processing may be collectively performed and the manufacturing process may be simplified.

2. Detailed Configuration Examples

is a plan view of a first detailed example of the embodiment. The first detailed example basically has the same configuration as the configuration example shown in, but is different in the configuration of the probe electrodes. Specifically, fixed electrodesare provided in the fixed electrode portionand movable electrodesare provided in the movable electrode portion, fixed electrodesare provided in the fixed electrode portionsand movable electrodesare provided in the movable electrode portions. The fixed electrode fixing portions,are aggregated inside of the movable body MB like those in the configuration example shown in, and the respective wires are provided on the wiring structure SA provided in the opening part OP. Note that, hereinafter, the fixed electrodes,are collectively referred to as “fixed electrodes”, the movable electrodes,are collectively referred to as “movable electrodes”, the fixed electrodes,are collectively referred to as “fixed electrodes”, and the movable electrodes,are collectively referred to as “movable electrodes”.

As described above, when an out-of-plane rotation Z-axis physical quantity sensor is used as the sensor of the MEMS device, the opening part OP is provided at the side with the smaller rotation torque of the movable body MB with respect to the rotation axis, and thereby, the rotation torque may be made smaller. Accordingly, the rotation torque of the whole movable body MB may be increased and higher sensitivity and downsizing can be realized. Further, the wiring structure SA provided under the routing portions of the respective wires is set at e.g., the ground and degradation of capacitance offset due to provision of an unnecessary capacitance between the probe electrodes may be suppressed.

is a schematic diagram of section structures of the first detailed example along dashed-dotted lines c, d in. The upper part ofcorresponds to the section along the dashed-dotted line c and shows the sectional shape cut along the fixing portionsand the supporting beams. In the sectional view along the dashed-dotted line c, the first wire Land the second wire Lare provided on the wiring structure SA via the insulating film D. The second wire Lextends in the opposite direction to the second direction DRalong the dashed-dotted line c and is electrically coupled to the movable body MB and the movable electrode portions,via the supporting beams. Further, the first wire Lis linearly provided from the fixed electrode fixing portionto the fixed electrode terminal Talong the first direction DR. The lower part ofcorresponds to the section along the dashed-dotted line d. As shown in, the respective wires are linearly provided along the wiring structure SA and extend. In the sectional view along the dashed-dotted line d, the first wires L, L, the second wire L, and the first wire Lare sequentially placed from the side in the second direction DR.

is a diagram for explanation of an intersection portion of the respective wires in the embodiment shown inetc. As shown in the upper part of, in the first detailed example, the wires including the first wires L, Land the second wire Lare provided and the number of wires is four in total. Of these wires, the two first wires Lare provided on the right end and the left end of the wiring structure SA or the shield structure SC in the plan view. Therefore, it is necessary to couple the two first wires Lacross the first wire Land the second wire Lplaced at the center of the wiring structure SA or the like. Here, in the embodiment, as shown in, a trench T is provided and the first wires Lare coupled via the shield structure SC. As shown in the upper part of, the trench structure has a rectangular shape in the plan view. As shown in the lower parts ofin sectional views along dashed-dotted lines e, f, the insulating film D is opened immediately beneath only the two first wires Lto be coupled and the wires are electrically coupled to the shield structure SC. Further, the two first wires Lare electrically coupled via the shield structure SC. The shield structure SC is electrically insulated from another portion of the shield structure SC by the groove of the trench T. In the sectional shape along the dashed-dotted line f shown in the lower part of, sectional shapes of the second wire Land the lower layers thereof are shown. The second wire does not intersect with the other wire and the insulating film D is not opened therefor.